下面列出了java.lang.invoke.LambdaForm.BasicType#basicType ( ) 实例代码，或者点击链接到github查看源代码，也可以在右侧发表评论。
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}
/**
* Adapts a target method handle by post-processing
* its return value (if any) with a filter (another method handle).
* The result of the filter is returned from the adapter.
* <p>
* If the target returns a value, the filter must accept that value as
* its only argument.
* If the target returns void, the filter must accept no arguments.
* <p>
* The return type of the filter
* replaces the return type of the target
* in the resulting adapted method handle.
* The argument type of the filter (if any) must be identical to the
* return type of the target.
* <p><b>Example:</b>
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
...
MethodHandle cat = lookup().findVirtual(String.class,
"concat", methodType(String.class, String.class));
MethodHandle length = lookup().findVirtual(String.class,
"length", methodType(int.class));
System.out.println((String) cat.invokeExact("x", "y")); // xy
MethodHandle f0 = filterReturnValue(cat, length);
System.out.println((int) f0.invokeExact("x", "y")); // 2
* }</pre></blockquote>
* <p> Here is pseudocode for the resulting adapter:
* <blockquote><pre>{@code
* V target(A...);
* T filter(V);
* T adapter(A... a) {
* V v = target(a...);
* return filter(v);
* }
* // and if the target has a void return:
* void target2(A...);
* T filter2();
* T adapter2(A... a) {
* target2(a...);
* return filter2();
* }
* // and if the filter has a void return:
* V target3(A...);
* void filter3(V);
* void adapter3(A... a) {
* V v = target3(a...);
* filter3(v);
* }
* }</pre></blockquote>
* @param target the method handle to invoke before filtering the return value
* @param filter method handle to call on the return value
* @return method handle which incorporates the specified return value filtering logic
* @throws NullPointerException if either argument is null
* @throws IllegalArgumentException if the argument list of {@code filter}
* does not match the return type of target as described above
*/
public static
MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
BoundMethodHandle result = target.rebind();
BasicType rtype = BasicType.basicType(filterType.returnType());
LambdaForm lform = result.editor().filterReturnForm(rtype, false);
MethodType newType = targetType.changeReturnType(filterType.returnType());
result = result.copyWithExtendL(newType, lform, filter);
return result;
}