test/hotspot/jtreg/runtime/jni/checked/libTestCheckedEnsureLocalCapacity.c

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#include <jni.h>
#include <stdio.h>

void reduceLocalCapacity(JNIEnv* env) {
    puts("reduceLocalCapacity: setting to 1");
    (*env)->EnsureLocalCapacity(env,1);
}

JNIEXPORT void JNICALL
Java_TestCheckedEnsureLocalCapacity_ensureCapacity(JNIEnv *env,
                                                   jobject unused,
                                                   jobject target,
                                                   jint capacity,
                                                   jint copies) {
  int i;
  printf("ensureCapacity: setting to %d\n", capacity);
  (*env)->EnsureLocalCapacity(env, capacity); // set high
  reduceLocalCapacity(env);     // sets low

  printf("ensureCapacity: creating %d LocalRefs\n", copies);
  for (i = 0; i < copies; i++) {
    target = (*env)->NewLocalRef(env, target);
  }

  puts("ensureCapacity: done");
}